| Abstract: | Abstract— It has been suggested that the formation of the 22 km diameter lunar crater Giordano Bruno was witnessed in June 1178 A.D. To date, this hypothesis has not been well tested. Such an impact on the Earth would be “civilization threatening”. Previous studies have shown that the formation of Giordano Bruno would lead to the arrival of 10 million tonnes of ejecta in the Earth's atmosphere in the following week. I calculate that this would cause a week‐long meteor storm potentially comparable to the peak of the 1966 Leonids storm. The lack of any known historical records of such a storm is evidence against the recent formation of Giordano Bruno. Other tests of the hypothesis are also discussed, with emphasis on the lack of corroborating evidence for a very recent formation of the crater. |
